Transpiration

Q. Which of the following is not a purpose of transpiration?

1. Supplying water for photosynthesis
2. Translocation of sugars from source to sink
3. Maintaining shape and structure of the plants
4. Transporting minerals from the soil to all parts of the plant

Q. Water vapor comes out from the plant leaf through the stomatal opening. Through the same stomatal opening, carbon dioxide diffuses into the plant during photosynthesis. Reason out the above statements using one of following options :

1. Both processes cannot happen simultaneously
2. Both processes can happen together because the diffusion coefficient of water and $C{O}_2$ are different.
3. One process occurs during day time and the other at night
4. The above processes happen only during night time.

Q.

How does relative humidity affect transpiration?

Q.

Is transpiration active or passive?

Q.

In which cell type the initial carboxylation reaction occurs in C₃ and C₄ plants?

Q. Cohesion-tension-transpiration pull model explains:

1. Conduction of food in plants
2. Transport of organic materials
3. Transpiration in plants
4. Water transport in plants

Q. Buttress roots

Q.

Describe the role of stomata in the process of transpiration.

Q.

What is the epidermal cell modification in plants which prevents water loss?

Q.

Which of the following molecules is produced during the light-dependent reactions of photosynthesis and used in the light-independent reactions?

1. carbon dioxide, NADPH, and ATP

2. oxygen, NADPH, and ATP

3. NADPH and ATP

4. oxygen and glucose

Q. Whose water potential is less than water potential of root hair during water absorption by root hair?

1. Gravitational Water
2. Soil solution
3. Pure water
4. Vacuolar sap

Q. Swollen leaf base is called

1. Petiolate leaf base
2. Sheathing leaf base
3. Stipulate leaf base
4. Pulvinous leaf base

Q.

During what stage of photosynthesis is O2 produced?

1. Cyclic photophosphorylation
2. The light-dependent reactions involving photosystems I and II
3. Carbon fixation
4. Non-cyclic photophosphorylation

Q. When transpiration is rapid

1. $\psi w$ of epidermal cells decreases
2. a negative pressure develops in xylem vessel
3. all of these
4. water is absorbed through the root passively

Q.

The ultimate cause for the movement of water against gravity in a tree is:

1. osmosis

2. transpiration

3. imbibition

4. photosynthesis

Q.

Ninety percent of the water lost by the plants during transpiration is through the _______________ of the leaf.

Q. Excessive loss of water causes wilting of leaves, it can be prevented by:

1. keeping the plant in bright light
2. spraying the plant with alcohol
3. applying vaseline on the leaf surface
4. adding high amounts of fertilizers to the soil

Q. Which of the following hormone closes stomata in response to water stress?

1. IAA
2. ABA
3. NAA
4. ${\text{GA}}_3$

Q. Which of the following will affect the active uptake of water?

1. Transpirational power of the root hairs
2. Typical tissue organization
3. Tension due to transpiration
4. Osmotic concentration of the cell sap of the leaves

Q.

Transpiration is manifestation of

1. turgor pressure

2. wall pressure

3. root pressure

4. None of these

Q.

The amount of water taken up by a plant can be investigated experimentally using a potometer. Refer to the following diagram showing a potometer to answer the following question.

What is expected to occur after the leafy shoot, together with the potometer, is placed in a dark, cool cupboard for one hour?

1. The air bubble in the capillary tube moves towards the leafy shoot at a faster rate

2. The air bubble in the capillary tube moves towards the leafy shoot at a slower rate

3. The air bubble in the capillary tube moves away from the leafy shoot

4. There is no observable change in the set-up

Q. Which one of the following is not a type of transpiration?

1. Cuticular transpiration
   
2. Lenticular transpiration
   
3. None of the above
4. Bark transpiration
   

Q.

Question 31

Transpiration is a necessary evil in plants. Explain

Q.

Given below is the diagram of an experimental set-up to study the process of transpiration in plants. Study the same and then answer the question that follows:

After about half an hour what change, if any, would you expect to find in the cobalt chloride paper placed on the dorsal and ventral sides of the leaf? Give a reason to support your answer.

Q.

In terrestrial areas, temperature and rainfall are affected by_______.

Q.

Conduction of food in plants takes place through………………

Q. Transpiration

1. supplies water for photosynthesis
2. All of the above.
3. transports minerals from the soil to all parts of the plant
4. helps in cooling

Q. As light intensity increases, rate of transpiration _______.

1. increases
2. decreases
3. remains same
4. remains unaffected

Q.

What are the cells that make the leaves curl in plants during water stress?

Q.

Name the following:

Permanently open structures seen on the bark of an old woody stem.